/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2005 Blender Foundation.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include "../node_shader_util.h"

/* **************** OUTPUT ******************** */

static bNodeSocketTemplate sh_node_volume_principled_in[] = {
	{	SOCK_RGBA, 1, N_("Color"),					0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f},
	{	SOCK_STRING, 1, N_("Color Attribute"),		0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f},
	{	SOCK_FLOAT, 1, N_("Density"),				1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1000.0f},
	{	SOCK_STRING, 1, N_("Density Attribute"),	1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f},
	{	SOCK_FLOAT, 1, N_("Anisotropy"),			0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f, PROP_FACTOR},
	{	SOCK_RGBA, 1, N_("Absorption Color"),		0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f},
	{	SOCK_FLOAT, 1, N_("Emission Strength"),		0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1000.0f},
	{	SOCK_RGBA, 1, N_("Emission Color"),			1.0f, 1.0f, 1.0f, 1.0f, 0.0f, 1.0f},
	{	SOCK_FLOAT, 1, N_("Blackbody Intensity"),	0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
	{	SOCK_RGBA, 1, N_("Blackbody Tint"),			1.0f, 1.0f, 1.0f, 1.0f, 0.0f, 1.0f},
	{	SOCK_FLOAT, 1, N_("Temperature"),			1000.0f, 0.0f, 0.0f, 0.0f, 0.0f, 6500.0f},
	{	SOCK_STRING, 1, N_("Temperature Attribute"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f},
	{	-1, 0, ""	}
};

static bNodeSocketTemplate sh_node_volume_principled_out[] = {
	{	SOCK_SHADER, 0, N_("Volume")},
	{	-1, 0, ""	}
};

static void node_shader_init_volume_principled(bNodeTree *UNUSED(ntree), bNode *node)
{
	for (bNodeSocket *sock = node->inputs.first; sock; sock = sock->next) {
		if (STREQ(sock->name, "Density Attribute")) {
			strcpy(((bNodeSocketValueString *)sock->default_value)->value, "density");
		}
		else if (STREQ(sock->name, "Temperature Attribute")) {
			strcpy(((bNodeSocketValueString *)sock->default_value)->value, "temperature");
		}
	}
}

static void node_shader_gpu_volume_attribute(GPUMaterial *mat, const char *name, GPUNodeLink **outcol, GPUNodeLink **outvec, GPUNodeLink **outf)
{
	if (strcmp(name, "density") == 0) {
		GPU_link(mat, "node_attribute_volume_density",
		         GPU_builtin(GPU_VOLUME_DENSITY),
		         outcol, outvec, outf);
	}
	else if (strcmp(name, "color") == 0) {
		GPU_link(mat, "node_attribute_volume_color",
		         GPU_builtin(GPU_VOLUME_DENSITY),
		         outcol, outvec, outf);
	}
	else if (strcmp(name, "flame") == 0) {
		GPU_link(mat, "node_attribute_volume_flame",
		         GPU_builtin(GPU_VOLUME_FLAME),
		         outcol, outvec, outf);
	}
	else if (strcmp(name, "temperature") == 0) {
		GPU_link(mat, "node_attribute_volume_temperature",
		         GPU_builtin(GPU_VOLUME_FLAME),
		         GPU_builtin(GPU_VOLUME_TEMPERATURE),
		         outcol, outvec, outf);
	}
	else {
		*outcol = *outvec = *outf = NULL;
	}
}

static int node_shader_gpu_volume_principled(GPUMaterial *mat, bNode *node, bNodeExecData *UNUSED(execdata), GPUNodeStack *in, GPUNodeStack *out)
{
	/* Test if blackbody intensity is enabled. */
	bool use_blackbody = (in[8].link || in[8].vec[0] != 0.0f);

	/* Get volume attributes. */
	GPUNodeLink *density = NULL, *color = NULL, *temperature = NULL;

	for (bNodeSocket *sock = node->inputs.first; sock; sock = sock->next) {
		if (sock->typeinfo->type != SOCK_STRING) {
			continue;
		}

		bNodeSocketValueString *value = sock->default_value;
		GPUNodeLink *outcol, *outvec, *outf;

		if (STREQ(sock->name, "Density Attribute")) {
			node_shader_gpu_volume_attribute(mat, value->value, &outcol, &outvec, &density);
		}
		else if (STREQ(sock->name, "Color Attribute")) {
			node_shader_gpu_volume_attribute(mat, value->value, &color, &outvec, &outf);
		}
		else if (use_blackbody && STREQ(sock->name, "Temperature Attribute")) {
			node_shader_gpu_volume_attribute(mat, value->value, &outcol, &outvec, &temperature);
		}
	}

	/* Default values if attributes not found. */
	if (!density) {
		static float one = 1.0f;
		density = GPU_constant(&one);
	}
	if (!color) {
		static float white[4] = {1.0f, 1.0f, 1.0f, 1.0f};
		color = GPU_constant(white);
	}
	if (!temperature) {
		static float one = 1.0f;
		temperature = GPU_constant(&one);
	}

	/* Create blackbody spectrum. */
	const int size = CM_TABLE + 1;
	float *data, layer;
	if (use_blackbody) {
		data = MEM_mallocN(sizeof(float) * size * 4, "blackbody texture");
		blackbody_temperature_to_rgb_table(data, size, 965.0f, 12000.0f);
	}
	else {
		data = MEM_callocN(sizeof(float) * size * 4, "blackbody black");
	}
	GPUNodeLink *spectrummap = GPU_color_band(mat, size, data, &layer);

	return GPU_stack_link(mat, node, "node_volume_principled", in, out, density, color, temperature, spectrummap,
	                                                           GPU_constant(&layer));
}

/* node type definition */
void register_node_type_sh_volume_principled(void)
{
	static bNodeType ntype;

	sh_node_type_base(&ntype, SH_NODE_VOLUME_PRINCIPLED, "Principled Volume", NODE_CLASS_SHADER, 0);
	node_type_socket_templates(&ntype, sh_node_volume_principled_in, sh_node_volume_principled_out);
	node_type_size_preset(&ntype, NODE_SIZE_LARGE);
	node_type_init(&ntype, node_shader_init_volume_principled);
	node_type_storage(&ntype, "", NULL, NULL);
	node_type_gpu(&ntype, node_shader_gpu_volume_principled);

	nodeRegisterType(&ntype);
}
